Display device and method of manufacturing the same

Abstract

A display device includes pixels disposed on a substrate. Each of the pixels include a pixel circuit layer disposed on the substrate and includes at least one transistor, a first electrode disposed on the pixel circuit layer and electrically connected to the at least one transistor, a bank disposed on the first electrode, the bank including an opening exposing the first electrode, a conductive pattern disposed on a side surface of the bank surrounding the opening of the bank and the exposed first electrode, a light-emitting element disposed on the conductive pattern in the opening of the bank and electrically connected to the first electrode, and a second electrode disposed on the light-emitting element. The conductive pattern is a guide member that guides light emitted from the light-emitting element to an upper portion of the second electrode.

What is claimed is: 
     
       1. A display device comprising: pixels disposed on a substrate, wherein each of the pixels includes: a pixel circuit layer disposed on the substrate and includes at least one transistor; a first electrode disposed on the pixel circuit layer and electrically connected to the at least one transistor; a bank disposed on the first electrode, the bank including an opening exposing the first electrode; a conductive pattern disposed on a side surface of the bank surrounding the opening of the bank and the exposed first electrode; a light-emitting element disposed on the conductive pattern in the opening of the bank and electrically connected to the first electrode; and a second electrode disposed on the light-emitting element, and the conductive pattern is a guide member that guides light emitted from the light-emitting element to an upper portion of the second electrode, wherein the first electrode includes a groove stepped from a surface of the first electrode toward the pixel circuit layer, and the groove corresponds to the opening of the bank. 
     
     
       2. The display device of  claim 1 , wherein
 the light-emitting element includes a first end portion and a second end portion in a length direction of the light-emitting element, 
 the first end portion contacts and is electrically connected to the conductive pattern, and 
 the second end portion contacts and is electrically connected to the second electrode. 
 
     
     
       3. The display device of  claim 2 , wherein
 the light-emitting element includes:
 a bonding electrode disposed at the first end portion of the light-emitting element, the bonding electrode contacting and electrically connected to the conductive pattern; 
 a third semiconductor layer disposed at the second end portion of the light-emitting element, the third semiconductor layer contacting and electrically connected to the second electrode; 
 a second semiconductor layer disposed on the bonding electrode; 
 a first semiconductor layer disposed between the third semiconductor layer and the second semiconductor layer; and 
 an active layer disposed between the first semiconductor layer and the second semiconductor layer, 
 
 the first semiconductor layer is an n-type semiconductor layer doped with an n-type dopant, and 
 the second semiconductor layer is a p-type semiconductor layer doped with a p-type dopant. 
 
     
     
       4. The display device of  claim 3 , wherein the conductive pattern is bonded to the bonding electrode of the light-emitting element. 
     
     
       5. The display device of  claim 4 , wherein
 the conductive pattern includes a first layer disposed on the first electrode and a second layer disposed on the first layer, 
 the first layer directly contacts the first electrode, and 
 the second layer directly contacts the bonding electrode. 
 
     
     
       6. The display device of  claim 5 , wherein each of the first layer and the second layer includes a metal that reflects a light emitted from the light-emitting element. 
     
     
       7. The display device of  claim 6 , wherein
 the first layer includes at least one metal selected from gold and tin, 
 the second layer includes at least one metal selected from titanium, copper, and nickel, and 
 the first layer and the second layer have different thicknesses. 
 
     
     
       8. The display device of  claim 2 , wherein an area of the conductive pattern disposed on the side surface of the bank has a gradient corresponding to an inclination angle of the side surface of the bank. 
     
     
       9. The display device of  claim 8 , wherein the area of the conductive pattern includes a protrusion protruding toward the second electrode. 
     
     
       10. The display device of  claim 2 , wherein each of the pixels includes an intermediate layer disposed between the bank and the second electrode in the opening of the bank. 
     
     
       11. The display device of  claim 10 , wherein the intermediate layer is a fixing member fixing the light-emitting element, the intermediate layer including an organic material that has adhesiveness and is cured by heat or light. 
     
     
       12. The display device of  claim 2 , wherein
 each of the pixels includes:
 an emission area including the light-emitting element; and 
 a non-emission area adjacent to the emission area, 
 
 the bank corresponds to the non-emission area, and 
 the opening of the bank corresponds to the emission area. 
 
     
     
       13. The display device of  claim 12 , wherein each of the pixels includes:
 a cover layer entirely disposed on the second electrode; and 
 an upper substrate disposed on the cover layer. 
 
     
     
       14. The display device of  claim 13 , wherein the upper substrate includes:
 a base layer disposed on the cover layer including a surface facing the light-emitting element; 
 a light conversion pattern disposed on the surface of the base layer to correspond to the emission area; and 
 a light blocking pattern disposed on the surface of the base layer to correspond to the non-emission area. 
 
     
     
       15. The display device of  claim 14 , wherein the light conversion pattern includes:
 a color filter disposed on the surface of the base layer; and 
 a color conversion layer disposed on the color filter with an insulating layer disposed between the color conversion layer and the color filter to correspond to the light-emitting element, and the color conversion layer including color conversion particles. 
 
     
     
       16. The display device of  claim 15 , wherein the light blocking pattern includes:
 a first light blocking pattern disposed on the surface of the base layer; and 
 a second light blocking pattern disposed on the insulating layer to correspond to the first light blocking pattern. 
 
     
     
       17. The display device of  claim 16 , wherein the upper substrate includes a capping layer entirely disposed on the color conversion layer and the second light blocking pattern. 
     
     
       18. The display device of  claim 1 , wherein the opening of the bank has a width greater than a width of the first electrode. 
     
     
       19. The display device of  claim 18 , wherein
 the pixel circuit layer includes a passivation layer disposed on the at least one transistor, and 
 the opening of the bank entirely exposes the first electrode and partially exposes the passivation layer. 
 
     
     
       20. The display device of  claim 19 , wherein the conductive pattern is disposed on the exposed first electrode and the exposed portion of the passivation layer. 
     
     
       21. The display device of  claim 1 , wherein the conductive pattern includes: a third layer disposed on the exposed first electrode and the side surface of the bank; a first layer disposed on the third layer; and a second layer disposed between the first layer and the light-emitting element, the third layer directly contacts the first electrode, and the second layer directly contacts the light-emitting element. 
     
     
       22. The display device of  claim 21 , wherein
 the third layer includes at least one metal selected from titanium, copper, and nickel, 
 the first layer includes aluminum, and 
 the second layer includes at least one metal selected from gold and tin. 
 
     
     
       23. The display device of  claim 22 , wherein the first layer is disposed on an uppermost layer on the side surface of the bank. 
     
     
       24. A display device comprising: pixels disposed on a substrate, wherein each of the pixels includes: a pixel circuit layer disposed on the substrate, the pixel circuit layer including at least one transistor; a first electrode disposed on the pixel circuit layer and electrically connected to the at least one transistor; a bank disposed on the first electrode, the bank including an opening exposing the first electrode; a conductive pattern disposed on a side surface of the bank surrounding the opening and the exposed first electrode; a light-emitting element disposed on the conductive pattern in the opening and electrically connected to the first electrode; and a second electrode disposed on the light-emitting element, the conductive pattern includes a third layer disposed on the first electrode, a first layer disposed on the third layer, and a second layer disposed on the first layer on the first electrode, the conductive pattern is a guide member that guides light emitted from the light-emitting element to an upper portion of the second electrode, and the second layer is a bonding member bonded to the light-emitting element. 
     
     
       25. A method of manufacturing a display device, the method comprising:
 forming at least one transistor on a substrate; 
 forming a first electrode electrically connected to the at least one transistor on the at least one transistor; 
 applying an insulating material layer and a photosensitive material layer on the first electrode and removing the photosensitive material layer on an area of the first electrode to form a photosensitive pattern exposing the insulating material layer; 
 removing the exposed insulating material layer using the photosensitive pattern as an etching mask to form a bank including an opening exposing the area of the first electrode; 
 forming a conductive layer entirely on the photosensitive pattern and the exposed area of the first electrode; 
 removing the photosensitive pattern and the conductive layer disposed on the photosensitive pattern through a lift-off to form a conductive pattern on the area of the first electrode; 
 applying, entirely, an intermediate layer material having fluidity on the conductive pattern and the bank; 
 disposing a transfer substrate, onto which at least one light-emitting element is transferred, on the substrate, bonding the light-emitting element and the conductive pattern, curing the intermediate layer material to form an intermediate layer, and then removing the transfer substrate; and 
 forming a second electrode on the light-emitting element and the intermediate layer, 
 wherein the conductive pattern is a guide member that guides light emitted from the light-emitting element to an upper portion of the second electrode. 
 
     
     
       26. The method of  claim 25 , wherein the light-emitting element includes:
 a bonding electrode that contacts the conductive pattern and is electrically connected to the conductive pattern; 
 a third semiconductor layer that contacts the second electrode and is electrically connected to the second electrode; 
 a second semiconductor layer disposed on the bonding electrode; 
 a first semiconductor layer disposed between the third semiconductor layer and the second semiconductor layer; and 
 an active layer disposed between the first semiconductor layer and the second semiconductor layer, 
 the first semiconductor layer is an n-type semiconductor layer doped with an n-type dopant, and 
 the second semiconductor layer is a p-type semiconductor layer doped with a p-type dopant. 
 
     
     
       27. The method of  claim 26 , wherein
 the conductive pattern includes a first layer disposed on the first electrode and a second layer disposed on the first layer, 
 the first layer directly contacts the first electrode, and 
 the second layer directly contacts the bonding electrode.